JP2007005394A - Method of manufacturing insulating film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an insulating film of which film characteristics are superior in moisture absorption resistance, mechanical strength, etc., as well as an insulating film which is realized by using the method, and an electronic device provided with the insulating film. <P>SOLUTION: The method of manufacturing an insulating film includes a step to form a coating film by using a film formation composite having a cage-type structure, and a step to employ chemical species that can be react with a hydroxyl group and allow the hydroxyl group in the coating film to be reacted with. The insulating film is obtained by using the method, and the electronic device includes such the insulating film. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an insulating film having good film properties such as low hygroscopicity, dielectric constant and mechanical strength used for electronic devices, and further, an insulating film obtained by using the manufacturing method, and the insulating film The present invention relates to an electronic device.

In recent years, in the field of electronic materials, with the progress of higher integration, more functions, and higher performance, circuit resistance and capacitor capacity between wirings have increased, leading to an increase in power consumption and delay time. In particular, an increase in delay time is a major factor in reducing the signal speed of the device and the occurrence of crosstalk. Therefore, in order to reduce the delay time and speed up the device, it is necessary to reduce parasitic resistance and parasitic capacitance. It has been. As a specific measure for reducing this parasitic capacitance, an attempt has been made to cover the periphery of the wiring with a low dielectric interlayer insulating film. In addition, the interlayer insulating film is required to have excellent heat resistance that can withstand post-processes such as a thin film forming process, chip connection, and pinning when manufacturing a mounting substrate, and chemical resistance that can withstand a wet process. Furthermore, in recent years, low resistance Cu wiring is being introduced from Al wiring, and along with this, planarization by CMP (Chemical Mechanical Polishing) has become common, and high mechanical strength that can withstand this process is high. It has been demanded.

Polybenzoxazole and polyimide are widely known as highly heat-resistant insulating films, but because they contain highly polar N atoms, they are satisfactory in terms of low dielectric properties, low moisture absorption, durability, and hydrolysis resistance. Nothing has been obtained.
In addition, many organic polymers are generally poorly soluble in organic solvents, and it is an important issue to suppress precipitation in coating solutions and the generation of bumps in insulating films. Therefore, if the polymer main chain is bent to have a bent structure, the glass transition point and the heat resistance are adversely affected, and it is not easy to achieve both.
Further, a highly heat-resistant resin having a polyarylene ether as a basic main chain is known (Patent Document 1), and the dielectric constant is in the range of 2.6 to 2.7. However, in order to realize a high-speed device, further reduction of the dielectric constant is desired.

Further, when the dielectric constant is further reduced, the problem of moisture absorption accompanying the surface oxidation of the insulating film becomes obvious. Even if the chemical structure of the insulating film is excellent in low hygroscopicity, a very small amount of moisture and very small amount of oxygen contained in the atmosphere of the film forming process are adsorbed on the insulating film, and in the subsequent heating process The surface oxidation reaction by these water and oxygen occurs, and a slight hydroxyl group is generated on the surface of the insulating film. Even if the amount of the hydroxyl group is small, it has the property of attracting a large amount of water in the atmosphere and hydrating it, thereby increasing the hygroscopicity. Moisture contained in the insulating film is known to cause an increase in the dielectric constant of the insulating film, oxidation of the barrier metal during wiring structure creation, peeling, etc. In order to suppress the hygroscopicity of the insulating film surface, There is a need for a technique to remove or inactivate. As a low dielectric constant material having a cage compound, there is an example in which a cage compound is added to an aromatic skeleton (Patent Document 2). The generation of hydroxyl groups in the film forming process described above is not taken into consideration, and there is a problem in terms of low hygroscopicity. As an example paying attention to the hydroxyl group which exists in the surface of an organic type film, there exists an example which tried to connect the hydroxyl group which exists in the diamond particle surface with a bridge | crosslinking molecule | numerator (patent document 3). In this technique, an excellent material in terms of mechanical strength can be obtained. However, in order to perform cross-linking between particles, it is necessary that a very large number of hydroxyl groups exist on the particle surface. Therefore, a large number of hydroxyl groups remain after crosslinking, which is problematic in terms of hygroscopicity.
US Pat. No. 6,509,415 US Patent Publication No. 2003/187139 JP 2002-289604 A

  The present invention relates to a method for producing an insulating film having good film properties such as moisture absorption resistance and mechanical strength for solving the above-mentioned problems, further relates to an insulating film obtained by using the manufacturing method, and further comprising the insulating film. The present invention relates to an electronic device.

式（Ｉ）中、
Ｒは水素原子、炭素数１〜１０のアルキル基、炭素数２〜１０のアルケニル基、炭素数２〜１０のアルキニル基、炭素数６〜２０のアリール基、または炭素数０〜２０のシリル基を表す。
ｍは１〜１４の整数を表す。
Ｘはハロゲン原子、炭素数１〜１０のアルキル基、炭素数２〜１０のアルケニル基、炭素数６〜２０のアリール基、または炭素数０〜２０のシリル基を表す。
ｎは０〜１３の整数を表す。
＜１２＞
カゴ型構造を有する化合物が窒素原子を有さないことを特徴とする＜１＞〜＜１１＞のいずれかに記載の絶縁膜の製造方法。
＜１３＞
＜１＞〜＜１２＞のいずれかに記載の絶縁膜の製造方法を用いて形成した絶縁膜。
＜１４＞
＜１３＞に記載の絶縁膜を有する電子デバイス。 It has been found that the above problems are solved by the following <1> to <14> configurations.
<1>
Forming a coating film using a film-forming composition containing a compound having a cage structure;
A method for producing an insulating film, comprising a step of reacting a hydroxyl group in the coating film with a chemical species capable of reacting with a hydroxyl group.
<2>
<1> above, wherein the chemical species capable of reacting with a hydroxyl group is a compound having two or more functional groups capable of reacting with a hydroxyl group and capable of reacting with a hydroxyl group in an insulating film to form a chemical bond. The manufacturing method of the insulating film of description.
<3>
The method for producing an insulating film according to the above <1> and <2>, wherein the chemical species having a functional group capable of reacting with a hydroxyl group is a compound having a functional group capable of reacting with a hydroxyl group.
<4>
<1> to <3>, wherein the step of reacting a hydroxyl group in the coating film is a treatment of exposing the coating film in a gas atmosphere containing 1% by volume or more of a chemical species capable of reacting with a hydroxyl group. The manufacturing method of the insulating film of description.
<5>
The process for reacting a hydroxyl group in a coating film is performed using a chemical species having a functional group capable of reacting with a hydroxyl group generated by plasma, and the production of an insulating film as described in <1> to <4> above Method.
<6>
The step of reacting a hydroxyl group in the coating film is a treatment of bringing the coating film into contact with a solution containing a chemical species capable of reacting with a hydroxyl group, according to any one of the above <1> to <3> Insulating film manufacturing method.
<7>
The method for producing an insulating film according to any one of <1> to <6>, wherein the cage structure is a saturated hydrocarbon structure.
<8>
<1> to <7>, wherein the ratio of the total carbon number of the cage structure to the total carbon number in the total solid content contained in the film-forming composition is 30% or more Of manufacturing an insulating film.
<9>
The method for manufacturing an insulating film according to any one of <1> to <8>, wherein the cage structure is an adamantane structure.
<10>
The method for producing an insulating film according to any one of <1> to <8>, wherein the cage structure is a diamantane structure.
<11>
The method for producing an insulating film according to <10>, wherein the compound having a cage structure is a polymer of at least one compound represented by the following formula (I).

In formula (I),
R is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group having 0 to 20 carbon atoms. Represents.
m represents an integer of 1 to 14.
X represents a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group having 0 to 20 carbon atoms.
n represents an integer of 0 to 13.
<12>
The method for producing an insulating film according to any one of <1> to <11>, wherein the compound having a cage structure does not have a nitrogen atom.
<13>
The insulating film formed using the manufacturing method of the insulating film in any one of <1>-<12>.
<14>
An electronic device having the insulating film according to <13>.

  The insulating film obtained by using the insulating film manufacturing method of the present invention has good film properties such as moisture absorption resistance and mechanical strength, and therefore can be used as an interlayer insulating film in electronic devices and the like.

  Hereinafter, the present invention will be described in detail.

<Compound having a cage structure>
The “cage structure” described in the present invention is such that the volume is determined by a plurality of rings formed of covalently bonded atoms, and a point located within the volume cannot be separated from the volume without passing through the ring. Refers to a molecule. For example, an adamantane structure is considered a cage structure. In contrast, a cyclic structure having a single bridge such as norbornane (bicyclo [2,2,1] heptane) is not considered a cage structure because the ring of a single bridged cyclic compound does not define volume. .

The total number of carbon atoms in the cage structure of the present invention is preferably 10 to 30, more preferably 11 to 18, and particularly preferably 14 carbon atoms.
The carbon atom here does not include a linking group substituted with a cage structure or a carbon atom of the substituent. For example, 1-methyladamantane is composed of 10 carbon atoms, and 1-ethyldiamantane is composed of 14 carbon atoms.

  The compound having a cage structure used in the present invention is preferably a saturated hydrocarbon, and preferable examples include diamond-like adamantane, diamantane, triamantane, tetramantane, dodecahedran, etc. in that it has high heat resistance. More preferred examples include adamantane, diamantane, and triamantane. Particularly preferred examples include diamantane in that a lower dielectric constant is obtained and synthesis is easy.

  The cage structure in the present invention may have one or more substituents. Examples of the substituent include a halogen atom (a fluorine atom, a chloro atom, a bromine atom, or an iodine atom), a carbon number of 1 to 10. Linear, branched and cyclic alkyl groups (methyl, t-butyl, cyclopentyl, cyclohexyl, etc.), alkenyl groups having 2 to 10 carbon atoms (vinyl, propenyl, etc.), alkynyl groups having 2 to 10 carbon atoms (ethynyl, phenyl) Ethynyl etc.), C6-C20 aryl groups (phenyl, 1-naphthyl, 2-naphthyl etc.), C2-C10 acyl groups (benzoyl etc.), C6-C20 aryloxy groups (phenoxy etc.) ), Arylsulfonyl groups having 6 to 20 carbon atoms (such as phenylsulfonyl), nitro groups, cyano groups, silyl groups (triethoxysilyl, methyldiethoxysilyl, Vinylsilyl etc.) and the like. Among these, preferred substituents are a fluorine atom, a bromine atom, a linear, branched or cyclic alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkynyl group having 2 to 5 carbon atoms, and a silyl group. is there. These substituents may be further substituted with another substituent.

  The cage structure in the present invention is preferably 1 to 4 valent, more preferably 2 to 3 valent, and particularly preferably 2 valent. At this time, the group bonded to the cage structure may be a monovalent or higher valent substituent or a divalent or higher linking group.

  The “compound having a cage structure” of the present invention may be a low molecular compound or a high molecular compound (for example, a polymer), and is preferably a polymer. When the compound having a cage structure is a polymer, the mass average molecular weight is preferably 1,000 to 500,000, more preferably 5,000 to 300,000, and particularly preferably 10,000 to 200,000. The polymer having a cage structure may be contained in the film forming composition as a resin composition having a molecular weight distribution. When the compound having a cage structure is a low molecular compound, the molecular weight is preferably 3000 or less, more preferably 2000 or less, and particularly preferably 1000 or less.

  In the present invention, the cage structure may be incorporated into the polymer main chain as a monovalent or higher pendant group. Preferred polymer main chains to which the cage compound is bonded include, for example, conjugated unsaturated bond chains such as poly (arylene), poly (arylene ether), poly (ether), polyacetylene, polyethylene, etc. Among them, heat resistance is good. From these points, poly (arylene ether) and polyacetylene are more preferable.

In the present invention, the cage structure is also preferably a part of the polymer main chain. That is, when it is a part of the polymer main chain, it means that the polymer chain is cleaved when the cage compound is removed from the polymer. In this form, the cage structures are directly single-bonded between the cage structures or linked by a suitable divalent or higher linking group. Examples of the linking group include, for example, —C (R ₁₁ ) (R ₁₂ ) —, —C (R ₁₃ ) ═C (R ₁₄ ) —, —C≡C—, arylene group, —CO—, —O—. , —SO ₂ —, —N (R ₁₅ ) —, —Si (R ₁₆ ) (R ₁₇ ) —, or a combination thereof. Here, R _{11 to} R ₁₇ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or an alkoxy group. These linking groups may be substituted with a substituent, and for example, the above-described substituents are preferable examples.
Among these, more preferred linking groups are —C (R ₁₁ ) (R ₁₂ ) —, —CH═CH—, —C≡C—, arylene group, —O—, —Si (R ₁₆ ) (R ₁₇ ). -Or a combination thereof, and particularly preferred are -CH = CH-, -C≡C-, -O-, -Si (R ₁₆ ) (R ₁₇ )-or a combination thereof.

  The “compound having a cage structure” in the present invention may contain one or more cage structures in the molecule.

  Specific examples of the “compound having a cage structure” in the present invention are shown below, but the present invention is of course not limited thereto.

  The compound having a cage structure used in the present invention is particularly preferably a polymer of a compound represented by the following formula (I).

In formula (I):
R represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group having 0 to 20 carbon atoms. And when R is other than a hydrogen atom, R may be further substituted with another substituent. Examples of the substituent include a halogen atom (fluorine atom, chloro atom, bromine atom, or iodine atom), alkyl group, alkenyl group, alkynyl group, aryl group, acyl group, aryloxy group, arylsulfonyl group, nitro group, cyano group. And a silyl group. R is preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms or a silyl group having 0 to 20 carbon atoms, more preferably a hydrogen atom or a silyl group having 0 to 10 carbon atoms. It is.
m represents an integer of 1 to 14, preferably an integer of 1 to 4, more preferably an integer of 1 to 3, and particularly preferably 2 or 3.
X represents a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group having 0 to 20 carbon atoms, and X represents another substituent. The above-mentioned thing is mentioned as an example of a substituent. X is preferably a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or a silyl group having 0 to 20 carbon atoms, more preferably a bromine atom or carbon. An alkenyl group having 2 to 4 carbon atoms, and a silyl group having 0 to 10 carbon atoms.
n represents an integer of 0 to 13, preferably an integer of 0 to 3, more preferably an integer of 0 to 2, and particularly preferably 0 or 1.

Optimum polymerization reaction conditions for the compound of formula (I) are preferably 0 to 220 ° C., more preferably 50 to 210 ° C., particularly preferably 100 to 200 ° C., preferably 1 in an organic solvent. It is preferable to carry out for -50 hours, more preferably 2-20 hours, 3-10 hours. If desired, a metal catalyst such as palladium, nickel, tungsten, or molybdenum may be used.
The preferable range of the weight average molecular weight of the polymerized polymer is 1000 to 500000, more preferably 5000 to 300000, and particularly preferably 10000 to 200000.

  Specific examples of the compound of formula (I) are shown below.

  The compound used in the present invention preferably has a reactive group that forms a covalent bond with other molecules by heat. Such a reactive group is not particularly limited, and for example, a substituent that causes a cycloaddition reaction or a radical polymerization reaction can be preferably used. For example, a group having a double bond (vinyl group, allyl group, etc.), a group having a triple bond (ethynyl group, phenylethynyl group, etc.), a combination of a diene group or a dienophile group for causing a Diels-Alder reaction is effective. In particular, an ethynyl group and a phenylethynyl group are effective.

  Further, the compound having a cage structure of the present invention preferably does not contain nitrogen atoms that increase the molar polarizability or cause the hygroscopicity of the insulating film to increase the dielectric constant. In particular, since a sufficiently low dielectric constant cannot be obtained with a polyimide compound, the compound having a cage structure of the present application is preferably a compound other than polyimide, that is, a compound having no polyimide bond or amide bond.

  From the viewpoint of imparting good characteristics (dielectric constant, mechanical strength) to the insulating film formed by using the production method of the present invention, the cage structure occupies the total number of carbons in the total solid content contained in the film-forming composition. The total carbon number ratio is preferably 30% or more, more preferably 50 to 95%, and still more preferably 60% to 90%. Here, the total solid content contained in the film-forming composition corresponds to the total solid content constituting the insulating film obtained by this coating solution. In addition, what does not remain in an insulating film after insulating film formation like a foaming agent is not included in solid content.

  The film-forming composition used in the present invention may contain an organic solvent as a coating solution, and may be used in the step of obtaining the coating film of the present invention. Examples of suitable solvents that can be used in the present invention are not particularly limited. For example, alcohol solvents such as methanol, ethanol, isopropanol, 1-butanol, 2-ethoxymethanol, and 3-methoxypropanol; acetone and acetylacetone Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, 2-pentanone, 3-pentanone, 2-heptanone, 3-heptanone, cyclohexanone; ethyl acetate, propyl acetate, butyl acetate, isobutyl acetate, pentyl acetate, ethyl propionate, propion Ester solvents such as propyl acid, butyl propionate, isobutyl propionate, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, γ-butyrolactone; diisopropyl ether, di Ether solvents such as tilether, ethylpropyl ether, anisole, phenetol, veratrol; aromatic hydrocarbon solvents such as mesitylene, ethylbenzene, diethylbenzene, propylbenzene, 1,2-dichlorobenzene, N-methylpyrrolidinone, dimethylacetamide, etc. Examples thereof include amide solvents, and these may be used alone or in admixture of two or more.

  More preferred solvents are acetone, propanol, cyclohexanone, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, γ-butyrolactone, anisole, mesitylene, and 1,2-dichlorobenzene.

  The solid content concentration of the coating solution used in the present invention is preferably 3 to 50% by mass, more preferably 5 to 35% by mass, and particularly preferably 7 to 20% by mass.

Furthermore, the coating solution used in the present invention does not impair various properties of the insulating film (heat resistance, dielectric constant, mechanical strength, coating property, adhesion, etc.), radical generators, nonionic surfactants, fluorine-based agents. You may add additives, such as a nonionic surfactant and a silane coupling agent.
Examples of the radical generator include t-butyl peroxide, pentyl peroxide, hexyl peroxide, lauroyl peroxide, benzoyl peroxide, azobisisobutyronitrile, and the like. Examples of the nonionic surfactant include octyl polyethylene oxide, decyl polyethylene oxide, dodecyl polyethylene oxide, octyl polypropylene oxide, decyl polypropylene oxide, dodecyl polypropylene oxide, and the like. Examples of the fluorine-based nonionic surfactant include perfluorooctyl polyethylene oxide, perfluorodecyl polyethylene oxide, perfluordecyl polyethylene oxide, and the like. Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, allyltrimethoxysilane, allyltriethoxysilane, divinyldiethoxysilane, trivinylethoxysilane, hydrolysates thereof, or The dehydration condensate of this thing etc. are mentioned.
The addition amount of these additives has an appropriate range depending on the use of the additive or the solid content concentration of the coating liquid, but generally 0.001% to 10% by mass% in the coating liquid, More preferably, it is 0.01% to 5%, and particularly preferably 0.05% to 2%.

<The process of forming a coating film using the film formation composition containing the compound which has a cage structure>
The coating film used in the present invention is a film-forming composition containing a compound having a cage structure, or a coating solution is applied to a substrate by any method such as spin coating, roller coating, dip coating, or scanning. Then, it can form by removing a solvent by heat processing. The method of the heat treatment is not particularly limited, but the generally used hot plate heating, a method using a furnace, light irradiation heating using a xenon lamp by RTP (Rapid Thermal Processor), etc. are applied. Can do.

  It is preferable to promote the crosslinking reaction by heating the coating film used in the present invention. The optimum conditions for this heat treatment are preferably a heating temperature of 200 to 450 ° C, more preferably 300 to 420 ° C, particularly preferably 350 to 400 ° C, and a heating time of preferably 1 minute to 2 hours, more The time is preferably 10 minutes to 1.5 hours, particularly preferably 30 minutes to 1 hour. The heat treatment may be performed in several stages. Moreover, you may use bridge | crosslinking means, such as electron beam irradiation and ultraviolet irradiation.

  Although there is no restriction | limiting in particular in the film thickness of the coating film used for this invention, It is preferable that it is 0.001-100 micrometers, It is more preferable that it is 0.01-10 micrometers, It is especially 0.1-1 micrometer. preferable.

In addition, a porous film can be formed by adding a foaming agent in advance to the coating solution used in the present invention. The foaming agent added to form the porous film is not particularly limited, and examples thereof include organic compounds having a boiling point higher than the solvent of the coating solution, thermally decomposable low molecular compounds, and thermally decomposable polymers. It is done.
The addition amount of the foaming agent has an appropriate range depending on the solid content concentration of the coating solution, but generally it is preferably 0.01% to 20%, more preferably 0.1% by mass% in the coating solution. -10%, particularly preferably 0.5% to 5%.

<Chemical species capable of reacting with hydroxyl groups>
The “chemical species capable of reacting with a hydroxyl group” described in the present invention refers to a chemical species that causes a dehydration reaction such as hydrogen radicals, hydrogen ions, and hydrogen molecules to remove the hydroxyl group itself, and a Si—OH group, Si—H group, Si— Has a functional group capable of reacting with a hydroxyl group such as X (X is a halogen element), alkoxysilyl group, Si—N bond, Si—O—Si bond, C—OH group, Si—OH group, COOH group, ester group And both compounds capable of reacting with hydroxyl groups in the insulating film to form chemical bonds. The effect of the present invention can be obtained as long as there is one functional group capable of reacting with a hydroxyl group within a chemical species capable of reacting with a hydroxyl group, but more preferably two or more, and particularly preferably three or more. The chemical species capable of reacting with a hydroxyl group preferably has a cyclic structure. Examples of the cyclic structure may be those composed of carbon typified by a benzene skeleton or a cyclohexane skeleton, or may be a cyclic structure composed of a repeating structure of Si—O bonds. Moreover, there may be a plurality of cyclic structures in one chemical species, and the types may be different. Examples of chemical species capable of reacting with a preferred hydroxyl group include hydrogen, hydrogen ion, hydrogen radical, hexamethyldisilazane (HMDS), 1,3-bis (4-biphenyl) -1,1,3,3-tetramethyl. Disilazane, hexachlorodisiloxane, tetraethoxysilane, methyltriethoxysilane, methyltrimethoxysilane, dimethyldiethoxysilane, dimethyldimethoxysilane, tetramethylcyclotetrasiloxane, 1,4bis (dimethylsilyl) benzene, 1,4bis (Hydroxydimethylsilyl) benzene, phenethyltrichlorosilane, cycloheptanecarboxylic acid, trans-1,2-cyclohexanediol, 9-hydroxyfluorene, tartaric acid and the like. Further, the chemical species capable of reacting with a hydroxyl group in the present invention can be used in any form such as a molecule, an oligomer, and a polymer. Since these chemical species react with the hydroxyl group generated in the film forming process to remove or form a new bond, moisture absorption by the hydroxyl group can be prevented. In addition, when the crosslinked structure is formed from two or more hydroxyl groups, the film strength can be improved.

<Step of reacting hydroxyl groups in the film using chemical species capable of reacting with hydroxyl groups>
The “step of reacting a hydroxyl group in a film with a chemical species capable of reacting with a hydroxyl group” in the present invention means that a substrate coated with the film-forming product of the present invention is exposed to a gas atmosphere containing a chemical species capable of reacting with a hydroxyl group. It is a process to do. As a method of realizing this process using a gas atmosphere, there is a method of introducing a substrate coated with the film-forming composition of the present invention into a container containing a vapor of a chemical species capable of reacting with a hydroxyl group. The vapor of the chemical species that can react with the hydroxyl group may be a mixture of a plurality of compounds, or may be diluted with an inert gas such as helium, argon, xenon, or nitrogen as necessary. The concentration of the gas containing a chemical species capable of reacting with a hydroxyl group is preferably 1 to 100% by volume, more preferably 5 to 50% by volume, and particularly preferably 10 to 20% by volume. Further, the substrate may be heated to promote the reaction of the hydroxyl group. The optimum conditions for this heat treatment are preferably 50 to 450 ° C, more preferably 100 to 400 ° C, and particularly preferably 200 to 350 ° C. Moreover, it is also preferable to perform this process under reduced pressure. The optimum pressure condition is preferably 13 to 101 kPa, more preferably 26 to 101 kPa, and particularly preferably 66 to 101 kPa. The time for the treatment with a gas containing a chemical species capable of reacting with a hydroxyl group is preferably 1 second to 10 minutes, more preferably 10 seconds to 5 minutes, and particularly preferably 30 seconds to 2 minutes.
This step can also be performed using a plasma atmosphere. For example, a substrate coated with the film-forming composition of the present invention is introduced into a commercially available parallel plate plasma apparatus, and a chemical species capable of reacting with a hydroxyl group represented by hydrogen is supplied to generate a plasma. This is achieved by exposing the chemical species generated by the plasma to the substrate. At that time, the substrate may be heated as necessary, and the optimum heating temperature is preferably from 0 to 400 ° C, more preferably from 0 to 350, and particularly preferably from 0 to 250 ° C. The plasma electron density suitable for this step is preferably 1E10 to 5E12 / cm ³ , more preferably 5E10 to 2E12 / cm ³ , and particularly preferably 1E11 to 1E12 / cm ³ . The treatment time suitable for this step is preferably 1 second to 3 minutes, more preferably 2 seconds to 1 minute, and particularly preferably 10 seconds to 30 seconds.
This step can also be performed using a solution of a chemical species that can react with a hydroxyl group. For example, a substrate coated with the film-forming product of the present invention may be immersed in a propylene glycol monomethyl ether acetate solution of a chemical species capable of reacting with a hydroxyl group, and the solution may be uniformly applied on the substrate using a spin coater. You may apply and perform a contact process. During the contact treatment, the solution may be heated or activated by ultrasonic waves or the like. The concentration of this solution is preferably 0.1 to 100% by mass, more preferably 0.1 to 5% by mass, and particularly preferably 0.1 to 1% by mass. After the contact treatment, washing may be performed using any solvent or solution as necessary. Further, after the contact treatment, heat treatment is preferably performed to promote the reaction with the hydroxyl group, and the optimum temperature is preferably 50 to 400 ° C, more preferably 100 to 350 ° C, particularly preferably 120 to 250 ° C. It is.
This step is preferably performed after the heating step for promoting the crosslinking reaction of the coating film is completed. In addition, there is no restriction | limiting in the frequency | count of performing this process, It is also possible to use two or more chemical species which can react with a hydroxyl group simultaneously.

  The film obtained by using the insulating film manufacturing method of the present invention is suitable as an insulating film in an electronic component such as a semiconductor device or a multichip module multilayer wiring board, and includes an interlayer insulating film for a semiconductor, a surface protective film, and a buffer coat film. In addition, it can be used as a passivation film in an LSI, an α-ray blocking film, a cover lay film of a flexographic printing plate, an overcoat film, a cover coat of a flexible copper-clad plate, a solder resist film, a liquid crystal alignment film, and the like.

<Evaluation of hygroscopicity>
In order to evaluate the hygroscopicity of the insulating film, it is possible to compare the dielectric constant measured immediately after forming the insulating film with the dielectric constant after adsorbing moisture. Since the dielectric constant of water is about 80, the dielectric constant of the insulating film increases when water is adsorbed. That is, it can be judged that an insulating film with a small increase in dielectric constant is a good insulating film with low hygroscopicity, and the increase in dielectric constant after moisture adsorption is 0.05 or less depending on the use of the insulating film. desirable. In order to adsorb moisture, it can be left in a normal atmospheric environment for a long time, but in order to shorten the time, an insulating film is placed in a high temperature and humidity environment and water vapor is actively adsorbed to the insulating film. It is also possible to perform accelerated evaluation.

  The following examples illustrate the invention and are not intended to limit its scope.

  The structures of the compounds used in the examples are shown below.

<Synthesis Example 1>
4,9-dibromodiamantane was synthesized by the method described in Macromolecules 1991, 24, 5266. A 500 ml flask was charged with 1.30 g of commercially available p-divinylbenzene, 3.46 g of 4,9-dibromodiamantane, 200 ml of dichloroethane, and 2.66 g of aluminum chloride, and stirred at an internal temperature of 70 ° C. for 24 hours. Thereafter, 200 ml of water was added to separate the organic layer. After adding anhydrous sodium sulfate, the solid content was removed by filtration, and dichloroethane was concentrated under reduced pressure until the volume was reduced to half, 300 ml of methanol was added to this solution, and the deposited precipitate was filtered. 2.8 g of polymer (A-4) having a weight average molecular weight of about 10,000 was obtained.
Similarly, a polymer (A-12) having a weight average molecular weight of about 10,000 was synthesized by Friedel-Crafts reaction.

<Example 1>
1.0 g of the above polymer (A-4) was dissolved by heating in a mixed solvent of 5.0 ml of cyclohexanone and 5.0 ml of anisole to prepare a coating solution. The solution was filtered through a 0.1 micron tetrafluoroethylene filter, spin-coated on a silicon wafer, and the coating film was heated on a hot plate at 150 ° C. for 60 seconds under a nitrogen stream, and then nitrogen in a clean oven. Heat treatment was performed at 400 ° C. for 1 hour in an atmosphere. Then, it introduce | transduced in the airtight container filled with HMDS vapor | steam, and performed 200 degreeC for 5 minute (s). The relative dielectric constant of the obtained insulating film having a thickness of 0.5 μm was calculated from the capacitance value at 1 MHz by using a mercury probe manufactured by Four Dimensions and an HP4285ALCR meter manufactured by Yokogawa Hewlett-Packard. Moreover, it was 8.7 GPa when the Young's modulus was measured using nano indenter SA2 by MTS. Thereafter, the film was allowed to stand for 24 hours in an environment of 121 ° C. and 95% humidity, and the dielectric constant increased by 0.01.

<Example 2>
The experiment was conducted in the same manner as in Example 1, and instead of introducing into a sealed container filled with HMDS vapor and heat treatment at 200 ° C. for 5 minutes, it was immersed in a 1% by mass HMDS propylene glycol monomethyl ether acetate solution for 30 seconds. Subsequently, it was washed with propylene glycol monomethyl ether acetate. Thereafter, heating was carried out in nitrogen at 200 ° C. for 10 minutes. The dielectric constant was 2.56 and the Young's modulus was 8.8 GPa. Thereafter, the film was allowed to stand for 24 hours in an environment of 121 ° C. and 95% humidity, and the dielectric constant increased by 0.02.

<Example 3>
The experiment was performed in the same manner as in Example 1, and instead of performing the introduction treatment and the heat treatment at 200 ° C. for 5 minutes in the sealed container filled with the HMDS vapor, it was applied to a hydrogen plasma (pressure 70 Pa 200 W) generated by a commercially available plasma apparatus for 10 seconds. When exposed, the dielectric constant was 2.57 and Young's modulus was 9.1 GPa. Thereafter, the film was allowed to stand for 24 hours in an environment of 121 ° C. and 95% humidity, and the dielectric constant increased by 0.01.

<Comparative Example 1>
When an experiment was conducted in the same manner as in Example 1 and the introduction treatment and the heat treatment at 200 ° C. for 5 minutes were not performed in a sealed container filled with HMDS vapor, the dielectric constant was 2.56 and the Young's modulus was 8.8 GPa. Thereafter, the film was allowed to stand for 24 hours in an environment of 121 ° C. and 95% humidity, and the dielectric constant increased by 0.11.

<Synthesis Example 2>
4,9-diethynyldiamantane was synthesized according to the synthesis method described in Macromolecules., 5262, 5266 (1991) using diamantane as a raw material. Next, 10 g of 4,9-diethynyldiamantane, 50 ml of 1,3,5-triisopropylbenzene and 120 mg of Pd (PPh ₃ ) ₄ were stirred at an internal temperature of 190 ° C. for 12 hours under a nitrogen stream. After the reaction solution was brought to room temperature, 300 ml of isopropyl alcohol was added. The precipitated solid was filtered and washed with methanol. 3.0 g of polymer (A) having a weight average molecular weight of 20000 was obtained.

<Example 4>
1.0 g of the polymer (A) synthesized in Synthesis Example 2 was dissolved in 10.0 ml of cyclohexanone to prepare a coating solution. The solution was filtered through a 0.2 micron tetrafluoroethylene filter, spin-coated on a silicon wafer, and the coating film was heated on a hot plate at 110 ° C. for 90 seconds under a nitrogen stream, and then at 250 ° C. for 60 seconds. Heating was further performed in a clean oven at 400 ° C. for 30 minutes in nitrogen. Then, it introduce | transduced in the airtight container filled with TMCTS vapor | steam, and heated at 200 degreeC for 5 minute (s). The obtained insulating film having a thickness of 0.5 microns had a dielectric constant of 2.35 and a Young's modulus of 9.2 GPa. Thereafter, the film was allowed to stand for 24 hours in an environment of 121 ° C. and 95% humidity, and the dielectric constant increased by 0.01.

<Comparative example 2>
When the experiment was conducted in the same manner as in Example 4 and the introduction treatment and the heat treatment at 200 ° C. for 5 minutes were not performed in a sealed container filled with TMCTS vapor, the dielectric constant was 2.46 and the Young's modulus was 7.1 GPa. After that, when allowed to stand for 24 hours in an environment of 121 ° C. and 95% humidity, the dielectric constant increased by 0.13.

<Comparative Example 3>
1.0 g of the polymer (B) (obtained from Sigma-Aldrich) was dissolved in 10.0 ml of cyclohexanone to prepare a coating solution. The solution was filtered through a 0.2 micron tetrafluoroethylene filter, spin-coated on a silicon wafer, and the coating film was heated on a hot plate at 110 ° C. for 90 seconds under a nitrogen stream, and then at 200 ° C. for 60 seconds. Heating was further performed in a clean oven at 400 ° C. for 30 minutes in nitrogen. Then, it introduce | transduced in the airtight container filled with TMCTS vapor | steam, and heated at 200 degreeC for 5 minute (s). The relative dielectric constant of the obtained insulating film having a thickness of 0.50 microns was 2.65. The Young's modulus was 4.3 GPa.
Thereafter, the film was allowed to stand for 24 hours in an environment of 121 ° C. and 95% humidity, and the dielectric constant increased by 0.11.

  As shown in Table 1, the insulating film obtained by using the present invention has a low dielectric constant, excellent mechanical strength, and particularly excellent moisture absorption resistance.

Claims (14)

  Forming a coating film using a film-forming composition containing a compound having a cage structure, and reacting a hydroxyl group in the coating film with a chemical species capable of reacting with a hydroxyl group. A method for manufacturing an insulating film.   2. The chemical species capable of reacting with a hydroxyl group is a compound having two or more functional groups capable of reacting with a hydroxyl group and capable of reacting with a hydroxyl group in an insulating film to form a chemical bond. Of manufacturing an insulating film.   The method for producing an insulating film according to claim 1 or 2, wherein the chemical species having a functional group capable of reacting with a hydroxyl group is a compound having a cyclic structure and a functional group capable of reacting with a hydroxyl group.   4. The insulation according to claim 1, wherein the step of reacting a hydroxyl group in the coating film is a treatment of exposing the coating film in a gas atmosphere containing 1% by volume or more of a chemical species capable of reacting with a hydroxyl group. A method for producing a membrane.   The method for producing an insulating film according to claim 1, wherein the step of reacting a hydroxyl group in the coating film is performed using a chemical species having a functional group capable of reacting with a hydroxyl group generated by plasma.   4. The insulating film according to claim 1, wherein the step of reacting a hydroxyl group in the coating film is a treatment of bringing the coating film into contact with a solution containing a chemical species capable of reacting with a hydroxyl group. Production method.   The method for manufacturing an insulating film according to claim 1, wherein the cage structure is a saturated hydrocarbon structure.   The insulation according to any one of claims 1 to 7, wherein the ratio of the total carbon number of the cage structure to the total carbon number in the total solid content contained in the film-forming composition is 30% or more. A method for producing a membrane.   The method for manufacturing an insulating film according to claim 1, wherein the cage structure is an adamantane structure.   The method for manufacturing an insulating film according to claim 1, wherein the cage structure is a diamantane structure. The method for producing an insulating film according to claim 10, wherein the compound having a cage structure is a polymer of at least one compound represented by the following formula (I).

In formula (I),
R is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group having 0 to 20 carbon atoms. Represents.
m represents an integer of 1 to 14.
X represents a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group having 0 to 20 carbon atoms.
n represents an integer of 0 to 13.   The method for producing an insulating film according to claim 1, wherein the compound having a cage structure does not have a nitrogen atom.   The insulating film formed using the manufacturing method of the insulating film in any one of Claims 1-12.   An electronic device having the insulating film according to claim 13.